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The differential diagnosis of headache and vertigo also includes a brainstem or cerebellar mass, hemorrhage, and infarction These uncommon disorders are best assessed by MRI Benign Paroxysmal Vertigo of Childhood Considered by many to be a form of migraine, benign paroxysmal vertigo of childhood is most common in children between the ages of and years Patients have recurrent attacks, usually one to four per month, and occasionally in clusters Onset is sudden—the child often cries out at the start of each episode— and is associated with emesis, pallor, sweating, and nystagmus Episodes are brief, lasting up to a few minutes, and may be mistaken for seizures Consciousness and hearing are preserved, and the neurologic examination is otherwise normal The electroencephalogram (EEG) is normal The disorder spontaneously remits after to years TABLE 24.2 COMMON CAUSES OF VERTIGO Suppurative or serous labyrinthitis Benign paroxysmal vertigo Migraine Vestibular neuronitis Ingestions Seizure Motion sickness TABLE 24.3 COMMON CAUSES OF PSEUDOVERTIGO Depression Anxiety Hyperventilation Orthostatic hypotension Hypertension Heat stroke Arrhythmia Cardiac disease Anemia Hypoglycemia Pregnancy Ataxia Visual disturbances Psychogenic disturbance Ototoxic Drugs Most agents that disturb vestibular function will also disturb auditory function Specific agents include aminoglycoside antibiotics, furosemide, ethacrynic acid, streptomycin, minocycline, salicylates, and ethanol Toxic doses of certain anticonvulsants and neuroleptics can produce measurable disturbances of vestibular function, although associated complaints of vertigo are rare Trauma Several mechanisms account for posttraumatic vertigo The most obvious is fracture through the temporal bone with damage to the labyrinth (see Chapters 106 ENT Trauma and 113 Neurotrauma ) Presentation includes vertigo, hearing loss, and hemotympanum CT scanning or MRI of the temporal bone should be obtained when there is hemotympanum or posttraumatic evidence of vestibular dysfunction More subtle causes of posttraumatic vertigo include trauma-induced seizures, migraine, or a postconcussive syndrome Vestibular concussion typically follows blows to parietooccipital or temporoparietal regions and presents with headache, nausea, vertigo, and nystagmus Although it generally remits with time, intermittent and recurrent episodes can occur Hyperextension and flexion (“whiplash”) injuries can be associated with vestibular dysfunction, probably caused by basilar artery spasm with subsequent impairment of their labyrinth and cochlear connections Symptoms may mimic basilar artery migraine or cerebellar stroke Seizures Two types of seizures are associated with vertigo: vestibular seizures (seizures causing vertigo) and vestibulogenic seizures (“reflex” seizures brought on by stimulating the semicircular canals or vestibules by sudden rotation or caloric testing) Vestibular seizures, the more common type, consist of sudden onset of vertigo with or without nausea, emesis, and headache, and are followed by loss or alteration of consciousness The EEG is abnormal and anticonvulsants may be of benefit Motion Sickness Motion sickness is precipitated by a mismatch in information provided to the brain by the visual and vestibular systems during unfamiliar rotations and accelerations The most common situation occurs when a child travels in a car or airplane and is deprived of a visual stimulus that confirms movement Symptoms include vertigo, nausea, and nystagmus Attacks can be prevented by allowing patients to watch the environment move in a direction opposite to the direction of body movement (such as encouraging a child to look out the window while riding in a car) Ménière Disease Uncommon in children younger than 10 years, Ménière disease is characterized by episodic attacks of vertigo, hearing loss, tinnitus, nystagmus, and autonomic symptoms of pallor, nausea, and emesis The underlying cause is believed to be an overaccumulation of endolymph within the labyrinth, which causes a rupture (endolymphatic hydrops) Typical attacks last from to hours and usually begin with tinnitus, a sense of fullness within the ear, and increasing hearing impairment The patient may have intermittent attacks for years, and there may be permanent hearing loss Miscellaneous Causes Vertigo may occur at any point in the clinical course of multiple sclerosis when the central demyelination interferes with the vestibular nuclei in the brainstem or its efferents or afferents Diagnosis is confirmed by MRI and lumbar puncture Paroxysmal torticollis of infancy consists of spells of head tilt associated with nausea, emesis, pallor, agitation, and ataxia Episodes are brief and self-limited and may recur for months or years The cause is unclear, although some authors see it as a prelude to benign paroxysmal vertigo Perilymphatic fistula is an abnormal communication between the labyrinth and the middle ear, with leakage of perilymphatic fluid through the defect It may be congenital or acquired by trauma, infection, or surgery The diagnosis may be suspected when vertigo and acute hearing loss is provoked by sneezing or coughing, actions that can increase perilymphatic drainage Diagnosis is confirmed by middle ear exploration Benign paroxysmal positional vertigo (BPPV) is rare in children, but has been reported in the literature in a patient as young as years old Patients typically complain of vertigo with changes in head position, especially upon waking in the morning and sitting up in bed Episodes usually last less than minute Finally, vertigo may be associated with diabetes mellitus and chronic renal failure EVALUATION AND DECISION Differentiation of True Vertigo and Pseudovertigo Evaluation of children with dizziness begins by distinguishing between those with true vertigo and those with pseudovertigo ( Tables 24.1 and 24.3 ) True vertigo is always associated with a subjective sense of rotation of the environment relative to the patient or of the patient relative to the environment All vertigo is made worse by moving the head, and acute attacks are usually accompanied by nystagmus True Vertigo History and Physical Examination Once true vertigo ( Fig 24.1 ) is identified, its severity, time course, and pattern must be established In general, the most severe attacks of vertigo have peripheral causes, whereas central causes tend to be more recurrent, chronic, and progressive Sudden onset of sustained vertigo suggests central or peripheral trauma, infection, stroke, or ingestion Recurrent episodic attacks suggest seizures, migraine, or benign paroxysmal vertigo More persistent episodes suggest brainstem or cerebellar mass lesions Recurrent, transient, altered mental status suggests seizure or basilar migraine Episodes of prior head injury suggest concussion syndromes Recent upper respiratory tract infections may suggest vestibular neuronitis History of ototoxic

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